Answer:

Explanation:
As we know that the displacement of the particle from the mean position is 1/5 times of its amplitude
so we have


so now we have

now we have

so the phase other particle in opposite direction is given as

so we have phase difference given as


Answer:
Acceleration of the car will be 
Explanation:
We have given mass of the ball m = 1600 kg
Force in north direction F= 7560 N
Resistance force which opposes the movement of car 
So net force on the car 
According to second law of motion we know that F=ma
So 

2m/s because the hockey puck is traveling at a constant speed ( acceleration is 0 ). Unless something acts on the hockey puck it will travel 2 m/s forever.
Answer:
battery .................